Diabetes Monitoring Methods

Continuous monitoring of the blood sugar is required for preventing the complications of diabetes. Modern technology and electronics has made this possible by introducing test equipment that can give digital displays on portable palm top devices. Urine and blood sugar measures are the most popular. However, a more detailed observation might be required to have quantitative estimates. We detail below some of the tools.

1. Urine Testing: It is the simplest possible test for diabetes. However, it is not very precise. The major limitation is that urine sugar will be positive only when the blood glucose level exceeds the kidney threshold. For most people this is when the blood sugar value is above 180 mg/dl and is much higher than the desired value between 60-120 mg/dl (optimal values vary) before meal. It thus helps only to monitor whether the blood glucose level exceeds the warning level. The second limitation is that hypoglycemia, low blood sugar values, that pose a greater danger than hyperglycemia can never be detected by testing urine sugar.

2. Blood Testing: Blood tests give more accurate estimates for blood sugar. Two different methods are used to develop handy instruments for measuring blood sugar. Photometric meters uses colour reflectance measures to detect the colour change on a strip pad caused by glucose in the blood. Electrochemical detection is an alternative method in that glucose in the blood causes a reaction on the test strip producing a tiny current. The meter detects the current and reports a digital test result. The optimal blood sugar (plasma glucose) values ranges from 60-120 mg/dl before meal and from 110-140 mg/dl after food for most people. Normal control is targeted to stabilise fasting blood sugar values around 95 mg/dl to avoid possible risk due to hypoglycemia.

3. C-peptide Measure: c-peptide is a substance that the pancreas releases into the bloodstream in equal amounts to insulin. Unlike insulin, it is not absorbed by the body and is washed out with urine. C-peptide levels show exactly how much insulin the body is making. Currently, tests based on the competition principle and the microtiter plate separation are available in kit form. However, the test can be done only in a well furnished lab.

4. Glycohemoglobin ($HbA_{1c}$) Measure: Glycohemoglobin measure is one of the most decisive measures indicating possible microvascular complications of diabetes. The procedure (HPLC method) has been difficult until hand held meters and cost effective reagents have appeared in the market recently. Monoclonal antibody method is used in these machines to quantitatively determine the glycohemoglobin contained in a drop of blood.